USING SEARCH ENGINES

A web search engine is designed to search for information on the World Wide Web. The search results are generally presented in a list of results and are often called hits. The information may consist of web pages, images, information and other types of files.

Web search engines work by storing information about many web pages. These pages are retrieved by a Web crawler - an automated Web browser which follows every link on the site. The contents of each page are then analyzed to determine how it should be indexed. Data about web pages are stored in an index database for use in later queries. The purpose of an index is to allow information to be found as quickly as possible. There are two main types of search engine indexes that have evolved: one is a system of predefined and hierarchically ordered keywords that humans have programmed extensively. The other is a system that generates an "inverted index" by analyzing texts it locates. This second form relies much more heavily on the computer itself to do the bulk of the work.

Search engines first became popular in the early 1990's. Around 2000, the Google search engine rose to prominence. The company achieved better results for many searches with an innovation called PageRank. This iterative algorithm ranks web pages based on the number and PageRank of other web sites and pages that link there, on the premise that good or desirable pages are linked to more than others. Google also maintained a minimalist interface to its search engine.

Search engines are the largest advertising companies in the world. They provide a link between companies selling products and services and buyers looking for them. Some employ the practice of allowing advertisers to pay money to have their listings ranked higher in search results. The search engines get paid by the companies every time a buyer is directed to their page. It is only pennies per hit, but there are millions of hits per day. Unlike newspapers and magazines the hits are from buyers interested in their products and they only pay for those hits. In addition, the products and services can be kept current to the minute and orders can be taken on line.

Those search engines which do not accept money for their search engine results make money by running search related ads alongside the regular search engine results. The search engines make money every time someone clicks on one of these ads.

Using for Research

Chances are that you have used the Google search engine to access information from the World

Wide Web. Did you find what you needed? Too much or too little or a lot of "irrelevant hits?" Your results may vary from search to search depending on what words you type and how they are entered.

Google and other commercial search engines like Yahoo, Ask.com and Bing allow users to

search for the occurrence of words across billions of Web pages. Web search engines are not very "intelligent"; they don't understand the context of your search or the subtle nuances of human language and thought. Remember, computers don't think, they are literal – they simply process commands -- therefore, the "intelligence" must come from you. The following "Google Tips" are designed to help search the Web more effectively. Almost all search engines use the same method to improve your search query, so the Google tricks will work with almost any search engine.

Tip #1 - Use Google Help (click on "About Google", "Google Web Search Features", "Basics of

Search"). In Google Help, you will find all sorts of nifty tricks to improve your searching. Go to the site for more detailed information about the following:

• Phrase search ("")
  By putting double quotes around a set of words, you are telling Google to consider the exact words in that exact order without any change.
• Search within a specific website (site:)
  Google allows you to specify that your search results must come from a given website. For example, [ iraq site:nytimes.com ]
• Terms you want to exclude (-)
  Attaching a minus sign immediately before a word indicates that you do not want pages that contain this word to appear in your results. The minus sign should appear immediately before the word and should be preceded with a space. For example, [ anti-virus -software ]
• Fill in the blanks (*)
  If you include *, or wildcard within a query, it tells Google to try to treat the star as a placeholder for any unknown term(s) and then find the best matches. For example, [ Google * ] or [ Obama voted * on the * bill ]
• Search exactly as is (+)
  Google employs synonyms automatically, so that it finds pages that mention, for example, childcare for the query [ child care ] (with a space), or California history for the query [ ca history ]. But sometimes Google helps out a little too much and gives you a synonym when you don't really want it. By attaching a +immediately before a word (remember, don't add a space after the +), you are telling Google to match that word precisely as you typed it. Putting double quotes around a single word will do the same thing.
• The OR operator
  Google's default behavior is to consider all the words in a search. If you want to specifically allow either one of several words, you can use the OR operator (note that you have to type 'OR' in ALL CAPS). For example,[ San Francisco Giants 2004 OR 2005 ] will give you results about either one of these years, whereas [ San Francisco Giants 2004 2005 ] (without the OR) will show pages that include both years on the same page. The symbol |can be substituted for OR. (The AND operator, by the way, is the default, so it is not needed.)

Tip #2 - Use the Advanced Search

You might want to try Advanced Search, which offers numerous options for making your searches more precise and getting more useful results. You can reach this page by clicking the Advanced Search link next to the search box on the Google home page. For example, you can set the Advanced Search to:

• contain ALL the search terms you type in
• contain the exact phrase you type in
• contain at least one of the words you type in
• do NOT contain any of the words you type in
• is written in a certain language
• is created in a certain file format
• was updated within a certain period of time
• contain numbers within a certain range
• within a certain domain, or website
• don't contain "adult" material

Tip #3 - Understand Your Results

Remember, any bozo with access to a Web server and some time on his hands can create a Web

page. As you access Web pages and retrieve information, constantly ask yourself, "Who wrote this, for what purpose, and for what audience?" Websites of any repute will clearly identify the author. In an academic setting, you are expected to use authoritative and scholarly sources. If you have questions about a site's content or motives, that's probably good enough reason to just skip it and move on.